To investigate fetal gene expression in obese women compared to lean women in the second trimester, Edlow et al. performed global gene expression analysis of amniotic fluid cell-free RNA. Samples were collected from women with a BMI ≥30 (obese) or <25 (lean) undergoing second trimester (14–24 weeks) genetic amniocentesis. Fetuses later found to have an abnormal karyotype were excluded from the study.

Tissue Condition Samples
Test amniotic fluid obese mother 8
Control amniotic fluid lean mother 8
Gene Fold Change (log2) Significance Genus Species